2 . One of Prague’s most famous sights, the Orloj, the third oldest clock in the world, has been stopped. It is set to undergo months of restoration (修复)that will see the return of several, but not all, of its original parts.

Perhaps no other clock better proves the genius of the early pioneers of time keeping than the Orloj. Marking the minutes and hours is only one of the many measurements it provides.

The 607-year-old astronomical clock tracks Old Bohemian time, when the new day begins with sunset; Babylon time, which tracks the day from sunrise to sunset; Central European time, which is marked with a hand in the shape of the sun; and Star time, measured by the way the stars appear to move because of the earth’s movement.

A calendar dial (刻度盘)notes the days of the week, month and year, and a zodiacal ring (黄道环)shows the path of the sun and the moon through the sky. But, it is the astrolabe (星盘)that is the heart of the clock’s mechanical (机械的) operation. It tracks the position of the sun, the moon and stars, and has been a necessary tool for astronomers.

Over the centuries, the clock has been damaged and repaired, but, always returned to fully working order. Its longevity has inspired a number of sayings. One is that when the clock stops running, the Czech land will be thrown into war and privation (贫困). Another holds that who ever tries to affect the machine will die or go crazy.

Skala, who has been a clock master for 25 years, said he was honored when asked to take care of the Orloj eight years ago. Asked whether he believed the sayings, Skala smiled. “I didn’t believe the stories,” he said, “or else I would never be able to work on the clock.”

Gulangyu Island, off the coast of Xiamen, Fujian, was certificated a world heritage site by UNESCO. Every year,     1     (million) of Chinese people visit Gulangyu Island     2     (enjoy) its natural delights and the     3     (combine) of foreign and Chinese architecture.

The recognition of this beautiful and     4     (cultural) remarkable island is     5     honor. But the fact that it is a heritage site means much more than that. The word “heritage” refers to the     6     (value) things we inherit from the past. And there are over 1,000 UNESCO’s world heritage sites,     7     (make) a rich tapestry (织锦) of memories, both natural and man-made. Just     8     a time machine, they take us back to our ancestors and even earlier, enabling us to wonder at both the natural world and human history.

Gulangyu Island and every world heritage item are worthy of care and protection. Since they came into existence, they     9     (remind) us of our rich and various cultural significance, and the things that made us     10     we are.

4 . One girl is being praised for a letter of apology she wrote to the rangers (园林管理员) at the National Parks Service (NPS). She reportedly _________ a rock home. In expressing her _________, the girl also returned the rock to the park. Later the NPS shared the letter on their Facebook page.

“Dear Park Ranger, I _________ like Tom Branch Falls,” the girl, named Karina, began her letter. “I love it so much that I _________ to take a souvenir home.”

“So I took a rock. I’m _________, and I want to return it,” she said. The heartfelt letter _________ with a postscript (附言) of “also look at the back”—where the girl _________ a picture of Tom Branch Falls. _________ for Karina, the park rangers were _________ by her sincere apology and even __________ back.

“Dear Karina, thank you for returning the rock! It has made its way back to Tom Branch Falls. If every __________ took a rock home, that would __________ 11 million rocks would be gone from the park every year,” the park officials wrote in their Facebook post.

“Now that you know to leave __________ the way you find it, we hope you will help share this __________ with others,” the officials wrote. “It is always a __________ thing to give others the chance to discover something meaningful!”

The Honghe Hani Rice Terraces(梯田), in southern Yunnan, China, cover a huge 16, 603-hectare area. The terraces,     1    (know)to all of the world now, were made out of a thick forest by the Hani people. The terraces rise at different angles from a shallow 15°    2     a steep 75°, forming a wonderful landscape(景观)that     3    (be)rare in the world.

In 2003, the terraced fields were     4    (official)recognized by UNESCO as a World Cultural and Natural Heritage site. About 1,300 years ago, the Hani people first     5    (come)to the steep mountains. They struggled against the difficult terrain(地形), successfully creating the terraces, where they grew rice in order to make     6    (they) living. Over the past 1,300 years, the Hani people have developed a complex system of channels     7    (bring)water from the forested mountaintops. They show great appreciation for natural phenomena such as rivers, mountains, the sun, fire     8     the moon. They have also created a complete farming system     9     involves cattle, ducks, and fish and supports the     10    (produce)of red rice, the area's main crop.

The landscape changes through the year. In April the terraces are all green as rice starts to grow; in later parts of the year it is yellowish brown as the rice ripens. In February, the terraces become bare earth, with the water reflecting(反射)the sky.

7 . One billion people in the world are short of water. How can this problem be solved. Some suggestions have been to desalinate ocean water or to build enormous water pipelines from areas where water is abundant. (Suggestions such as these prove extremely expensive when they are actually used.) One possibility that scientists are considering is pulling icebergs from either the North Pole or the South Pole to parts of the world with a water shortage. Although many questions must be answered before such a project could be tried, moving icebergs seems a reasonable possibility in the future.

Engineers, mathematicians, and glaciologists from a dozen countries have been considering the iceberg as a future source of water. Saudi Arabia is particularly interested in this project because it has a great water shortage. Scientists estimate that it would take 128 days to transport a large iceberg (about 1/2 square mile) to Saudi Arabia. Yet the iceberg would be completely melted by the 104th day. Therefore, insulation would be essential, but how to insulate the iceberg remains an unsolved problem.

The problems in transporting an iceberg are numerous. The first problem is choosing the iceberg to pull. The icebergs that form in the North Pole are quite difficult to handle because of their shape. Only a small portion extends above the water — most of the iceberg is below the surface, which would make it difficult to pull. South Pole icebergs, on the other hand, are flat and float like table tops. Thus they would be much easier to move.

How can a 200-million-ton iceberg be moved. No ship is strong enough to pull such enormous weight through the water. Perhaps several ships could be used. Attaching ropes to an iceberg this size is also an enormous problem. Engineers think that large nails or long metal rods could be driven into the ice. What would happen if the iceberg splits into several pieces during the pulling. Even if an iceberg with very few cracks were chosen, how could it be pulled through stormy waters. Furthermore, once the iceberg reached its destination, very few ports would be deep enough to store it.

All of these problems must be solved before icebergs can become a reasonable source of water. Yet scientists estimate that it will be possible to transport them in the near future. Each year, enough icebergs form to supply the whole world with fresh water for a full year. In addition, icebergs are free and nonpolluting. As a solution to the world’s water problems, icebergs may be a workable possibility.